Antifreezing liquid



Patented Sept. 28, 1937 UNITED STATES PATENT OFFICE.

2.094.504 am'mnnnzme LIQUID Otto Schenck, Dessan, and Walter Gellendlen, Berlin-Charlottenburg, Germany, assi'gnors to Deutsche Hydrierwe Berlin-Charlottenburg, Germany, a corporatier! of German! No Drawing. Application December 24, 1935, Se-

rlal No. 56,076. In Germany November 13,

2 Claims. (01. asss) There has been proposed a great number of substances to be used as means to avoid freezing of the confining liquids in gas meters, cooling liquids in motor-coolers of automobiles and 5 so on either alone or in most cases as an addi-- factory proved to be glycerol and ethylene glycol.

These substances however also in aqueous solutions, particularly at low temperatures are rather viscose which is a drawback in practical working.

Now it has been found, that the hydrogenation products of furfurol. i. e. iuriuryl alcohol and in particular tetrahydroiurfuryl alcohol are very good antifreezing means alone or in mixture with the splitting of! products which are produced simultaneously in small amount by energetic hydrogenation, as pentandiol and amyl alcohol. Furfuryl alcohol and tetrahydrofur- Iuryl alcohol are miscible with water in any ratio and lower essentially the freezing point of it already after addition 01 small quantities.

A mixture of three parts 01' water and one part 01' tetrahydrofuriuryl alcohol allows of cool-- ing down to -8 C. before crystallization ensues. A mixture of two parts of water and one part of tetrahydrofurfuryl alcohol crystallizes not before -15 C. By mixing the aqueous solutions 35 oi. the above named hydrogenation products with liquid organic compounds such as methanol, ethanol, butanol; amyl alcohol, ethylene glycol, propylene glycol, butylene glycol. glycerol, the

40 mono-alkyl-ethers oi glycol and glycerol, the

freezing point or the liquids may still further be lowered.

As compared with other antii'reezing means of an alcoholic nature the hydrogenation products of iuriurol are regarding corrosion .by no means inferior and maybe rendered easily fast to corroding by addition of known means such as the soluble salts of benzoic, salicyclic or olelc acid in an amount of less than one percent. Being of a minor viscosity they are most fit for gas meters.

Example 1 An excellent antifreezingllquid for motorcoolers of automobiles is obtained by mixture of one part by volume of tetrahydrofurfuryl alcohol and one part by volume water. This mixture allows of cooling down to ---20 C. before crystallization occurs.

Example 2 By mixing of one part of tetrahydrofuriuryl alcohol, half a part of ethylene glycol and two parts of water one obtains an antlireezing liquid which may be used as confining liquids for gas meters.

We claim:

1. The method of preventing freezing and cor-' rosion in the aqueous systems 01' gas meters and internal combustion engines which comprises using as the liquid thereof a solution of furiuryl alcohol and water.

2. The method of preventing freezing and corrosion in the aqueous systems of gas meters andinternal combustion engines which comprises using as the liquid thereof a solution of furifuryl alcohol and water in about equal proportions.

o'r'ro seamen. WALTER 

